Each year, old industries keep expanding and new ones are created. In
many of these, the use of hoists, tackle, rope transmissions, etc. is
ever increasing in extent and importance. Information on the selection
and use of ropes and tackles and the tying of knots is very scattering
and incomplete. The purpose of this bulletin is to collect information
from all the different sources possible and assemble it under one
cover, in the hope that it may be valuable to people in many different
fields of activity. It is not meant to be an advanced treatise for
those who consider themselves already proficient in the use of rope and
tackle but is designed as an aid and reference to those less skilled in
the art.
A variety of knots and splices are shown with occasional suggestions as
to their use and application. Some knots tie easily and are very secure
but are not so easy to untie; others are easily and quickly tied--are
secure and yet are not difficult to untie. Some knots are suitable for
small cords only, and others are adapted to large ship’s hawsers. For
these and other reasons, it is desirable to select the right knot for
the job in hand.
Nearly every individual at some time or other has gone camping. If he
chanced to select a remote or inaccessible mountain side for a vacation
trip, he probably had one or more pack animals to take in the supplies
and camp outfit. How many could use the famous Diamond hitch to fasten
the pack on the horse’s back so that it will not shift or fall off in
transit?
The desirability of correct selection with reference to the work to be
done is also true of tackle sets. One type of tackle will give great
mechanical advantage, but requires an excessive amount of rope or
requires frequent overhauling to complete the job, while another type,
using the same equipment, will not give such great mechanical advantage
but does not require overhauling so often during the progress of the
load.
Rope is coming more and more into favor for the transmission of
power--replacing gears and heavy leather belts. It is important that
the proper sized sheave wheel be used with a rope of given diameter in
order to secure the longest service from the transmission. It is also
important that speed be considered in the calculation for necessary
strength to transmit a certain amount of power. It is evident from
these two instances alone that it is desirable that the selection of
a rope transmission should be governed by the use of complete sets of
data on the subject.
Some of the knots, splices, etc. shown in this bulletin were found to
have more than one name, or were called by different names by different
authors. In such case only the most commonly used term was selected.